Monday, July 18, 2011

This is 60 MHz frequency meter / counter for measuring frequency from 10 Hz to 60 MHz with 10 Hz resolution. The meter provides very stable readings and has excellent input sensitivity thanks to on board amplifier and TTL converter, so it can even measure weak signals from crystal oscillators. With the addition of prescaller it is possible to measure the frequency of 1GHz and above.

The basic idea comes from the AN592 Microchip application note: "Frequency counter using PIC16C5x" where you may find a simple software wich implements a frequency counter using a PIC microcontroller.I wrote a specifically designed software to improve the counter resolution, to handle the IF mode and value by means of an operating menu, to decode and edit the read frequency on an LCD display. The result was a simple and effective device.

Sunday, July 17, 2011

More and more experiments are now ‘PC-assisted.’ Also conventional acquisition systems are very expensive. Since portable PCs are today common and a USB link is a better solutionhere we present an oscilloscope using USB port of the PC that operates at up to 10 kHz with ±16V input voltage. It has much more improved features than the PC-based oscilloscope . The oscilloscope uses IC PIC18F2550 from Microchip as the main controller, which makes the oscilloscope compact as there is no need of additional power supply for the entire circuit board.

Circuit description

At the heart of this oscilloscope is USB2.0-compliant microcontroller PIC18F2550 from Microchip. You can also use IC18F2445 in place of PIC18F2550. Specifications of this microcontroller are:-

Features of 18F2550

Programming

1. Up to 32 kB of flash memory, 2kB RAM and 256-byte EEPROM

2. Extended instruction set (optimised for ‘C’ compiler)

3. 8x8 single-cycle multiplier

4. Single-supply serial programming and easy debugging

USB transceiver

1. USB1.1 and 2.0 from 1.5 MB/s to 12 MB/s

2. Isochronous, bulk and interrupt transfer modes

3. 1 kB of access RAM usable with 32 endpoints (64 bytes each)

Multiple oscillator and power modes

1. From internal 31 kHz to external 48 MHz with PLL

2. Possible software switching between ‘run,’ ‘idle’ and sleep

modes. In sleep mode, current is down to 0.1 μA.

3. Wide operating voltage range (2.0V to 5.5V). Useful for battery

operations.

Complete set of classical peripherals

1. Several input/output (I/O) ports, four timers with capture/

compares

2. Synchronous and asynchronous enhanced modules

3. Streaming parallel port

4. 10-bit ADC module with up to 13-channel multiplexer.

This microcontroller has a USB2.0-compliant transceiver and a CPU running up to 12 MIPS.

The PICkit™ 2 Programmer/Debugger is a low-cost development tool with an easy to use interface for programming and debugging Microchip’s Flash families of microcontrollers. The full featured Windowsprogramming interface supports baseline, mid-range, PIC18,8-bit, 16-bit, and 32-bit microcontrollers, and many Microchip Serial EEPROM products. With Microchip’s powerful MPLAB Integrated Development Environment (IDE) the PICkit 2 enables in circuit debugging on most PIC microcontrollers. In-Circuit-Debugging runs, halts and single steps the program while the PIC microcontroller is embedded in the application. When halted at a breakpoint, the file registers can be examined and modified.

Features1. This device will work like the normal pickit2.
2. This wll work for any pic (5 and 3.3V devices)3. No mosfets no complex, only one voltage boost circuit.4. you can program the target without PC.

Simple Steps to made This programmer

Step 1:-

Download:Firmware and circuit
The following packages include circuit and firmware.
Firmware is the software which going to be burn into programmer's microcontroller, this firmware have code to enable the programmer to communicate with pc via usb and target microcontroller.
Click This link to dwonload the Firware and circuit Pickit 2 clone files

you can also download the firmware form the microchip web site.For Supported device listPlease refer to Readme.txt and pickit 2 user manual for details on building, installing and using Pickit 2.

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About Me

I m a Electronics/Software Design Engineer.
Anybody have questions about Embedded system design and software system design may ask questions here. if you have custom project in mind please ask for quote.